wn seedlings. The Chinese and Japanese chestnut in my
hands has made a very poor root stock for the American chestnut or its
hybrids. The European chestnut is only fair, with the chinquapin
somewhat better, but having the disadvantage of being troublesome to get
from the seed. The American chestnut, or its American hybrids, is by far
the best, providing we can get one with immunity. I think the Rochester
will shortly fill this need.
The chestnut oak has made a rather interesting stock for a few
varieties, notably a Chinese and 20 No. 3, a native American chestnut
sent to me from Bloomsburg, Pa. I now have a few of these double grafted
with other varieties.
I might say that I am no longer interested in any chestnut, no matter
how resistant it may be, unless the nut is of large size and fine
quality, because I can immunize a plant bearing a good size, fine
quality chestnut much easier and in a shorter time than one can be
developed through hybridization from an inferior nut. I am usually, like
most folks, looking for the path of least resistance.
My work has been a good deal divided during the past few years because,
while I started out with the chestnut alone, now I am carrying a dozen
other fruits, nuts and berries.
In closing let me state that my principle of induced immunity is sound
and the procedure feasible and practical.
* * * * *
THE PRESIDENT: About the result of grafting the chestnut on a
species of oak. How long have these scions been growing?
DR. ZIMMERMAN: About three years.
MR. HERSHEY: How long?
DR. ZIMMERMAN: This is not the oak that I had reference to
when you were up there. These are about three years old. I think they
grow a little better than on the chestnut. Many of them died. I have
another scheme now; that is grafting the scions as high as I can. Get
them united and then bend them over and get them to root. Some are doing
nicely, others have died.
DR. SMITH. I think you complimented us by thinking we could
follow you. Do you intend to vaccinate the chestnut and make it immune
and then expect it to transmit that immunity in its seed? Have you
checked up in the second generation?
DR. ZIMMERMAN: I haven't had time yet.
DR. SMITH: Thus far you have established immunity in the living
tree?
DR. ZIMMERMAN: Yes, and I have a bunch of seedlings now from
nuts from immunized trees that I planted last spring. I have 200 of
those. I expect them to in
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